Learn About The Importance Of Field Olfactometry

The Nasal Ranger
Field Olfactometer

The Iowa DNR has certified 34 odor inspectors trained by St. Croix Sensory, a Lake Elmo, Minnesota-based laboratory that specializes in odor analysis and taste and sensory testing. Training them cost about $15,500, with another $66,000 spent on equipment.

Nasal Rangers must have a good, but not too sensitive, sense of smell, said Charles McGinley, technical director and co-owner of St. Croix Sensory, which has certified more than 2,000 inspectors throughout the world.

Recruits are tested, using a series of felt-tipped markers containing varying levels of the chemical butenol. Blindfolded, the recruit must be able to pick the middle of the spectrum. The test is repeated three times for accuracy, McGinley said.

Once selected, the inspector gets a few days of training using an olfactometer, a device that resembles a radar gun held to the nose, and then receives a certificate and Nasal Ranger patch.